How to extract XML data from CLOB data type field in oracle table?

In short, we can extract XML data from CLOB data type field of oracle database table using the following SQL statement:

select XMLTYPE(CLOB COLUMN).EXTRACT('//Node1/Node2/text()') .getStringVal() from table_name.

Example:
SELECT XMLTYPE(t.request).EXTRACT('//destAccount/instId/text()').getStringVal() dest_id
  FROM FTTB_OUT_CUSTOM t
   WHERE t.Txn_date BETWEEN :FROMDATE AND :TODATE
  AND t.NOTIFICATION_STATUS='F'